But beyond the debate over whether Al Qaeda is a mortally wounded beast or a Hydra with still-potent force and a capacity for self-renewal is another question: What is the impact of systematically removing the idea men of what is essentially an ideology?

Eliminating Al Qaeda’s inspirational figures is important because it denies the movement its best communicators with potential recruits both near and far, many counterterrorism experts say. In the case of an al-Awlaki, they add, that means his demise is likely to have greater impact on Al Qaeda’s inspirational reach than on its prospects in the country where he was based.

“They’ve hit a great propagandist – and propaganda is important – so in that sense this is a big setback for Al Qaeda,” says Bruce Riedel, a former CIA officer who is now an intelligence and terrorism expert at the Brookings Institution in Washington.

On the other hand, Mr. al-Awlaki was less instrumental to the future of Al Qaeda in the Arabian Peninsula (AQAP), Mr. Riedel says. So no one should expect this blow to mean much in Yemen, which he describes as a country “collapsing into civil war” – the kind of chaos Al Qaeda thrives on.

“He was not the head of AQAP, he wasn’t its deputy, and he wasn’t its bombmaker,” he says. “So while this was a good thing to accomplish, AQAP remains a growth industry, and this isn’t going to change that one iota.”

Since the US special forces raid into Pakistan in May that took out Osama bin Laden, a number of US officials and counterterrorism experts have speculated that Al Qaeda increasingly resembles a spent force.

Defense Secretary Leon Panetta said shortly after taking his job in July that the US is “within reach of strategically defeating Al Qaeda.” Earlier this month, CIA Director David Petraeus told Congress that the loss for Al Qaeda of not just Mr. bin Laden but leaders like Atiyah Abdul Rahman (in August) had opened “an important window of vulnerability” for the terror organization.

Even counterterrorism experts who warn that Al Qaeda’s weakness is being overplayed – especially in a tumultuous Arab world – say that al-Awlaki’s death is significant, in part because of his influence outside the region.

Al-Awlaki was born in New Mexico and raised in Yemen before returning to America from 1991 to 2002 to get a bachelor's degree in civil engineering and a master's in education. He also served as a Muslim imam in California and Virginia.

After leaving the US, he is known for having communicated by e-mail with US ArmyMaj. Nidal Hasan, who is accused of killing 13 people at Fort Hood in 2009. He also met with Umar Farouk Abdulmutallab, the Nigerian Christmas Day bomber who tried to bring down an airliner over Detroit by setting off explosives concealed in his underwear. Mr. Abdulmutallab briefly took English classes in Sana’a, Yemen.

What made al-Awlaki’s reputation was the native English speaker’s ability to communicate with a broad audience and his grasp of technological skills. His renown in the West probably overplays his importance, Mr. Boucek says, but al-Awlaki’s particular skills were still important to Al Qaeda.

“He wasn’t the best theologian, but he could switch easily from perfect English to Arabic, with all the references from the Quran you could want,” Boucek says. “I don’t think we can dismiss the impact of that.”

Al-Awlaki was the thinker behind the glossy Al Qaeda magazine “Inspire,” a periodical that endeavored to explain the world’s upheaval and put it in the context of jihad. Like the al-Awlaki sermons that are easily found on the Internet, “Inspire” appealed to young alienated Muslims in a way that the rants of Ayman al-Zawahiri – the gray-bearded Egyptian who took over Al Qaeda’s leadership after bin Laden – could not, experts say.

Al-Awlaki’s cover story in the spring edition of “Inspire” stands out, Brookings’s Riedel says, for the manner in which it explains how events in the Arab World are ultimately playing out in Al Qaeda’s interest. The cover says simply “Tsunami.”

“He put a spin on the Arab Awakening that was promising for Al Qaeda – that said all the allies of America in this battleground of Al Qaeda are falling, and that it’s just a matter of time before our enemies aren’t going to be around and we’ll be able to move in to pick up the pieces,” Riedel says. “Losing such a narrator, someone who could interpret events in such a cogent manner, is significant for an organization like Al Qaeda.”

Indeed, some experts consider that, in the long run, the major impact of Friday’s strike may be the mortal blow it delivered to “Inspire.” Reports circulated after the initial news of al-Awlaki’s death suggested that the vehicle hit by the drone strike also contained Samir Khan, another American convert to jihad who co-produced the magazine.

“These were the brains behind ‘Inspire,’ a very powerful tool that answered all the questions anyone thinking about jihad might have to ask, like, ‘Why should I become involved in this?’ ” Carnegie’s Boucek says. “If that’s gone now, that’s something we shouldn’t downplay.”

Still, Boucek says the loss of one particularly inspirational leader may not, in the end, weigh much against the Arab world’s upheaval. “We are only at the beginning of the transformation in the region,” he says. “It’s way too early to be talking about the end of Al Qaeda.”